Manufacture of articles made under heat and pressure



Patented May 23, 1933 UNITED STATES PATENT OFFICE GAMIIQLE DREYFUS, OIBASEL, SWITZERLAND, ASSIGNOR '10 CELANESE OOBZPOBA'IION OF AMERICA, ACORPORATIOH OF DELAWARE MANUFACTURE 01 ARTICLES MADE UNDER HEAT ANDPRESSURE No Drawing.

This invention relates to the inanufac ture of pressed and mouldedarticles having a basis of or containing organic esters or ethers ofcellulose, hereinafter referred to as organic derivatives of cellulose,and in particular to the manufacture of pressed 4 and moulded articleshaving a basis of or containing cellulose acetate.

I have found that acetate of cellulose can Such softening or plasticinducing substances are for example triacetin, camphor,

isomeric xylene low carbon alkyl sulfonamids, diethylphthalate,triphenyl phosphate, tricresylphosphate, mannol, resorcin diacetate,mirbene oil, glycerine, or others having a plastic inducing action onthe organic. cellulose derivative, whi le appropriate vehicles for theplasticizing agents are for example, benzol, alcohol-benzol mixtures,water-benzol mixtures, water-alcohol benzol mixtures, water-alcoholmixtures, petrols', glasolines, benzines, toluol and others. Whilealcohol may be used alone as :1. vehicle for the plasticizing agent itis not very satisfactory for the obtainment of good homogeneous mouldedarticles.

If, for instance, cellulose acetate-powder is treated with a mixture oftriphenyl phosphate plus triacetin plus alcohol, a powder is obtainedafter evaporation of the alcohol which when subjected, for instance in amould, to heat and pressure, will give moulded articles but does notgive a good omogeneous article.

I have found, however, that in replacing alcohol in this case, bybenzol, or by water plus alcohol benzol, or by water plus ben-Application filed January 18, 1922. Serial No. 530,170.

zol, or by water plus alcohol, a powder is obtained after drying whichwith low heat of approximately 120 C. and a low pressure, givesanexcellent moulded sheet or block, or other article.

E wample 1 100 parts cellulose acetate powder are thoroughly treatedwith a mixture of 140 parts Water, 10 parts triphenylphosphate, 30 partsof triacetin, 12.5 parts of alcohol, and 12.5 parts of benzol. Then thewhole mixture is allowed to dry. The dry powder obtained can bepressedunder heat into sheets, blocks, or articles of all kinds, and

,the products so obtained-are, besides other qualities, very strong,tough and homogeneous.

Ewcmnple 2 100 parts of cellulose acetate powder are thoroughly treatedwith a mixture of 30 parts of triacetin, ten parts of camphor,

plus benzol as a vehicle, e. g., 165 parts. Again a powder is obtainedafter evapora- Ewample 3 100 parts cellulose acetate powder arethoroughly treated with a mixture of 20 parts of triacetine, 10 artsisomeric xylene monomethylsulfonamid: 10 parts of camphor plus benzol asa vehicle, e. g., 165 parts. After evaporation of the benzol a powder isobtained giving, under heat and pressure, sheets, blocks or otherarticles of all kinds having ver and homogeneity. nflammable characterof the camphor can be reduced by addition of triphenylphosphate,tricresyl phosphate or other phosphates or appropriate substances.

Example 4 100 parts cellulose acetate powder are thoroughly mixed with 5parts glycerine in 140 parts water and the Water then evaporemarkablestrength can be varied in different directions both as to the quantitiesemployed and as to the substances used.

In addition or instead or partly instead of the glycerine, triacetin,triphenylphosphate, camphor, or other plasticizing agents particularlyspecified in the above examples, other similarly acting substances ormixtures of substances can be used in appropriate quantities, to obtaina desired moulded or pressed article, and in varying those quantities arange varying from very hard to very soft moulded or pressed articles orsheets can be obtained according to the quantity of the substances soadded.

In addition to the substances mentioned in the above examples,stabilizers can be added, such as urea or urea derivatives, acetanilideor other stabilizing substances or mixtures thereof.

In addition to or instead or partly instead of benzol, water, alcohol,in the above examples (or their modifications) diluents such as petrols,gasolines, benzines, toluol, or other appropriate vehicles can be used,whether of organic or inorganic nature, or mixtures thereof.

I In addition to or instead or partly instead of acetate of cellulosepowder in above examples (or in their modifications) other organiccellulose ester powders, or cellulose ether powders, can be used.

The powdered cellulose acetate or other organic cellulose derivative canbe mixed with desired quantities or mixtures of metal powders,pulverized filling materials, pigments, mineral powders, soluble dyes,insoluble dyes, dye stufis, mica, fibrous materials, or otherappropriate materials, and then be heated and pressed into sheets, orblocks, or other moulded or pressed articles of all kinds. (This mixturecan be. made before or after the treatment of cellulose acetate powderwith a vehicle containing the camphor, camphor substitutes or otherplastic inducing agent.)

Very good p'ressings or mouldings are obtained in the'presence of,approximately 5% of water in the powders subjected to the pressing ormoulding.

Hollow mouldings or pressings can be executed if desired, by insertionof core pieces, linings, and the like, or the' pressings or mouldingscan be executed in such a way that the core pieces remain in, or are apart of the moulded or pressed sheet,

block or other article, be it that the core pieces consist of thread,wire, nettings, sheets, fabrics, or bodies. of any kind in metal,cotton, silk,-wood, paper, cardboard,

compositions, ebonite, or any other appropriate material.

The powders or mixtures of powders obtained according to .the abovedescription, can be pressed in heated moulds or press devices of anydescription, to produce blocks, sheets or articles of all kinds, or theycan likewise be pressed under heat into articles or on top of articlesof other materials in any other appropriate fashion, adheringpermanently to such articles or materials. For instance, the powders canbe spread on a sheet of fabric, paper, cardboard or metal, or on a sheetof other material or on an. article, and pressed on by a roller or otherdevice, the roller or device being heated up to the appropriatetemperature, and so for instance, different layers of fabrics or othermaterials alternating with layers of above powders can be superposed andpressed under heat into compound sheets, blocks, in-

sulating pipes, or other pipes, phonograph records or other articles ofall kinds.

The sheets, articles, blocks, or other articles, obtained according tothe present invention, can be easily machined, twisted, cut, drilled,bent, or otherwise worked and especially when heated to an appropriatetemperature. These articles can be reinoulded or repressed'into otherarticles when heated again underpressure.

On the other hand, the pressed or moulded material or articles obtainedby the present invention can be transformed when heated up to anappropriate temperature into blown articles, by the well-known blowingmethods. It is further very interesting that the acetate powders or theonce pressed or moulded materials as prepared according to abovedescription, can be pressed (if heated at the same time) through holesor open dies, and all kinds of pipes, rods, filaments, or other shapedarticles 'can be extruded in this way.

It is further of interest that no seasoning is required and all thearticles obtained according to above description are ready for use rightaway after the pressing or mouldmg. i

What I claim and try to secure by Letters Patents is:

1. A process of preparing a molding powder comprising treating anorganic derivative of cellulose in finely divided form with a mixture ofa plasticizing agent and a substantial quantity of a volatile liquidthat is a vehicle for the plasticizing agent" and is a non-solventforthe organic derivative of cellulose and evaporating the liquid vehicleat least partially.

2. A process of preparing a molding powder comprising treating celluloseacetate in finely divided form with a mixture of a plasticizing agentand a substantial quantity of a volatile. liquid that is a vehicle forthe plasticizing agent and is a non-solvent for substantial quantity .isa vehicle for thethe cellulose acetate 1 and evaporating the liquidvehicle at least partially. p

. 3. A process of preparing a molding powder comprising treating an oranic derivative of cellulose in finely divi ed form with a mixture of aplasticizing agent and a substantial uantity of a volatile liquid thatis a vehic e for the plasticizing agent and is a non-solvent for theorganic derivative of cellulose, which liquid vehicle contains water,vehicle at least partially.

4. A process of preparing a molding powder comprising treating an oranic derivative of cellulose in finely divided form with a mixture ofa-plasticizing agent and a of a volatile liquid that plasticizing agentand is a non-solvent ,for the orgamcderivative of cellulose, whichliquid vehicle contains water, and evaporatingthe vliquid vehicle untilthe roduct contains substantially about 5% 0? water.

- 5. A process of preparing a moldin powder comprising treating anorganic erivative of cellulose in finely divided form with a mixture ofa plasticizing agent and a volatile liquid that is a vehicle for the.lasti* cizing agent and is anon-solvent fort e organic, derivative ofcellulose in amount greater than that' of the organic derivative ofcellulose and evaporating the liquid vehicle at least partially; 6.Process of preparing a molding an pressing powder comprisin mixingsubstantially 100 arts-0f a pow ered organic de-' rivative o cellulosewith substant1ally 140 parts of water and a-plasticizing agent.

7. Process of preparing a moldin and pressing powder comprising mixin sustan-' tially 100 arts of a owdere organic derivative 0 cellulose witsubstantially 140 evaporating the water until tains substantially 5% ofwater.

8. Process of preparing a molding and pressing powder comprising mixingsu stanv tially 100 parts of'a powdered cellulose acetate withsubstantially 140 parts of water and a plasticizing agent.

9. Process of preparing a mol pressing powder comprising mixin tially100 parts of a wdered celF and su stan- 140 parts of water and aplasticizing agent and evaporating the water until the powder containssubstantially 5% of water.

process of preparing a molding pow 10. A der comprising treatingcellulose acetate in finely divided form with a mixture of aplasticizing agent and a substantial quantity of i a, volatile liquidthat is a vehicle for the plasticizing agent and is a non-solvent forthe cellulose acetate which liquid vehicle con and evaporating theliquiduloseacefinely divided form with a mixture of a plasticizing agentand a. substantial quantity of a volatile liquid that is a vehlcle forthe plasticizing agent and is a non-solvent for the cellulose acetatewhich liquid vehicle contains benzol and evaporating the liquid vehicleat least partially.

In testimony whereof I. have hereunto subscribed my name.

CAMILLE DREYFUS.

- parts of water and a, plasticizing agent and the powder con- 7 Aprocess of preparing a molding pow 'der comprising treating celluloseacetate m

